Wiring up Radiator Fans

All model Subarus, especially the older MY and L Series models, greatly rely on their electric radiator cooling fans during slow 4WD work. A good upgrade to give the fans more power, (which translates into more air flow and hence better cooling) is to directly wire the fans straight off the battery via a relay. For best results use 3mm wiring.

The standard radiator sensor should still be used, so the fans will still start up at the set temperature, and the dash -mounted over-ride switch will still work as it can be used in the new wiring. This method of wiring up the fans avoids a lot of the power loss that can occur in the main wiring loom.

(Please note: This information and the wiring diagram below are given in good faith.  The article's author and the club do not accept any liability for the use of this information.  All electrical work should be performed by a qualified auto electrician).

Here's the wiring diagram.